The present invention relates to the operation of electrostatic actuators, and more particularly, but not exclusively relates to simultaneous actuation and sensing techniques for such devices.
In Microelectromechanical Systems (MEMS), electrostatic drives, such as comb drives, typically rely on different actuation and sensing structures for feedback control. Separate actuation and sensing structures tend to undesirably add to the moving mass of the device—potentially resulting in a decrease of the device resonant frequency and correspondingly the operational frequency range of the device. Also, separate structure can lead to additional flexures, such as hinges or leaf springs, that add mechanical resistance and correspondingly reduces the displacement range of the device. Alternatively or additionally, existing schemes tend to be exceedingly complex, require incorporation of materials unfriendly to standard MEMS device fabrication techniques, and/or utilize more device “real estate” than is otherwise desired. Thus, there is an ongoing demand for further contributions in this area of technology.